gpio: driver for AMD Promontory

This patch adds a new GPIO driver for AMD Promontory chip.

This GPIO controller is enumerated by ACPI and the ACPI compliant
hardware ID is AMDF030.

Change history:

v2: 1. fix coding style
    2. registers renaming
v3: 1. change include file
    2. fix coding style
    3. remove module_init/exit, add module_platform_driver
    4. remove MODULE_ALIAS
v4: 1. change TOTAL_GPIO_PINS to PT_TOTAL_GPIO
    2. remove PCI dependency in Kconfig
    3. fix subject line

Signed-off-by: YD Tseng <Yd_Tseng@asmedia.com.tw>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 77a796d..6fed6fc 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -119,6 +119,13 @@
 
 	  If driver is built as a module it will be called gpio-altera.
 
+config GPIO_AMDPT
+	tristate "AMD Promontory GPIO support"
+	depends on ACPI
+	help
+	  driver for GPIO functionality on Promontory IOHub
+	  Require ACPI ASL code to enumerate as a platform device.
+
 config GPIO_BCM_KONA
 	bool "Broadcom Kona GPIO"
 	depends on OF_GPIO && (ARCH_BCM_MOBILE || COMPILE_TEST)